Transmission and clutch control



April 25, 1950 E. E. w'EMP TRANSIISSION AND CLUTCH CONTROL 7Sheets-Shea?l 1 Filed Nov. 20, 1944 WEMP AND CLUTCH CONTROL 8 2 M t s, 0.n 5, .a 2 a m s .7

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TRANSMISSION Filed Nov. zo. 1944 INVENTOR. Ernes Lf. Wav/7,0

April 25, 1950 E, E, wEMP 2,505,448

I l TRNSHISSION AND CLUTCH CONTROL Filed NOV. 20, 1944 7 Sheets-Sheet 3Eltc'ron Leven UIREc'nou Leven.

E. E. wEMP mmsurssrou AND cLuTcH comer.

April 25, 1950 Filed Nov. zo, i944 "7 sheets-sheet 4h IN1/EN Ton. .ErnesWemp IEz April 25, 1950 E. E. WEMP TRANSMISSION AND CLUTCH CONTROL FiledN ov. 20, 1944 '7 Sheets-Sheet 5 /45 I', /28 l" /4/ g2 75 I [40 0a. o c

INVENroR. Eme t'. Wemp A135125, 1950 E. E. WEMP TRANSMISSION AND CLUTCHCONTROL 7 Sheets-Sheet 6 Filed Nov.` 20,v 1944 Patented Apr. 25, 1950UNITED sTATEs PATENT OFFICE TRANSMISSION AND CLUTCH CONTROL Ernest E.Wemp, Detroit, Mich.

Application November 20, 1944, Serial No. 564,216

'1 claims. l

This invention relates to a transmission of power and it has to doespecially with a mechanism particularly adapted for use in anautomotive vehicle.

The general object and intention of the invention is to provide amechanism which embodies a gear change transmission for effectingvarious gear ratios between the engine of an automotive vehicle and thetraction wheels, together with means for controlling the transmissionand for otherwise controlling and governing the power transmitting lineor torque line, so that the operation of the mechanism in the vehicle isgreatly simplified, requiring a minimum of functions and duties of theoperator and. in effect, making the operation of the mechanism and thevehicle and the gear changing functions of a semiautomatic nature. Tothese ends a mechanism constructed in accordance with the inventionembodies a number of elements, such as an automatic clutch whichadvantageously and preferably is a centrifugal clutch, a power couplerwhich is capable of establishing a connection in the torque transmittingline while both the driving member and the driven member of the powercoupler are under a torque load, a gear change transmission which may beof a conventional nature. In conjunction with these elements. there is acontrolling system which may be, and preferably is hydraulic, and thissystem, in its fullest form, performs controlling functions on the gearchange transmission, the power coupler and theclutch.

The mechanism provides for the changing of the gear ratios in asemi-automatic` manner, without requiring an over-expensive orcomplicated gear change transmission, and at the same time it provides awide latitude for the exercise of the operators individual judgement anddesires. The centrifugal clutch 'is one which remains disengaged atnormal engine idling speeds and, therefore. is disengaged when theVehicle is at rest. The invention includes an arrangement, whereby upontowing or pushing ofthe vehicle, the engine may be turned over and tstarted even though the centrifugal clutch is normally disengaged whilethe engine is at rest. While the invention is especially adapted for usein automotive vehicles and `is so disclosed herein, the invention may beemployed in other places where similar conditions exist. Other objectsand advantages of the invention will be brought out as the detaileddescription is vconsidered in conjunction with the accompanyingdrawings:

Fig. 1 is aview largely in cross section showing (Cl. HD2-.073)

such parts as the centrifugal clutch, the power coupler, thetransmission. and associated controlling elements.

Fig. 2 is a detailed sectional view taken substantially on line 2-2 ofFig. 1 showing a clutch retractor spring.

Fig. 3 is a sectional view taken substantially on line 3--3 of Fig. 1showing an emergency oneway drive coupling.

Fig. 4 is a side elevational View of the clutch housing and transmissionand illustrating some of the controlling mechanism which is operated bythe driver or operator of the vehicle.

Fig. 5 is a sectional view taken substantially on line 5-5 of Fig. 4showing some of the control levers.

Fig. 6 is a sectional view taken substantially on line 6-6 of Fig. 1showing some of the hydraulic control system and the control valves.

Fig. 7 is a sectional view taken substantially on line 1-1 of Fig. 6looking to the right as Fig. 6 is viewed.

Fig. 8 is a sectional view similar to Fig. '1 but reversed in position.

Fig. 9 is a sectional view taken substantially on line 9-9 of Fig. 6looking to the right as Fig. 6 is viewed, showing the control cylinderfor the transmission.

Fig. 10 is a cross sectional view similar to Fig. 9 Vbut reversedrelative to Fig. 9.

Fig. l1 is a vsectional view taken substantially on line Ii-Il of Fig. lshowing the pump and high pressure line of the hydraulic system.

Fig. l2 is adetailed sectional view showing the cylinder head for theclutch controlling cylinder and showing the liquid line.

Fig. 13 is `a sectional view taken substantially on line Iii-I3 of Fig.6 showing one of the control valves in the hydraulic system and the lowpressure controlling valve.

Fig. 14 is a sectional view taken substantially on line |4-i4 of'Fig. 6illustrating the limited movement of one of the controlling valves.

Fig. 15 is a sectional view taken substantially on line llii5 of Fig. 6showing other control valves in the hydraulic system.

Fig. 15a is a diagrammatic view showingthe position of ports in theselector valve when the valve is in a neutral position.

Fig. 15b is a view similar to Fig. 15a showing the position ofports inthe selector valve when it is shifted to second gear position.

Fig. 15e is a diagrammatic view similar to Figs. 15a and 15b showingposition of ports in the selector valve when it is shifted to third gearposition.

Fig. 16 is a. sectional view taken substantially on line lli-I6 of Fig.6 illustrating further controlling valves.

Fig. 17 is a sectional view taken substantially on line |1-I1 of Fig, 6showing some of the structure of the valves shown in Figs. 16 and 17.

Fig. 18 is a sectional view of the power coupler in engaged condition.

Fig. 19 is a. sectional view similar to Fig. 18 showing the powercoupler in disengaged con-I dition.

Fig. 20 is a sectional view taken substantially on line 20-20 of Fig. 18showing the synchronizing parts of the power coupler.

Fig. 21 is a view similar to Fig. 20 showing the parts in anotherposition.

Referring first to Fig. 1, the crank shaft of an engine is shown at Iand it carries a ily wheel 2. The centrifugal clutch constructionincludes a cover plate 3 secured to the fly wheel and which carrieslevers 4 having unbalanced centrifugal masses and lever tips 6. Theswinging movement of the levers serve to shift the pressure plate 1 tothe left as the ligure is viewed, through the means of struts 8. In thisaction, a clutch driven disc having suitable facings thereon, as shownat 9, is frictionally engaged between the pressure plate and the ilywheel. The driven disc is drivingly mounted upon a clutch shaft I0, oneend of which is piloted in the y wheel, as at Il, and the other end ofwhich extends through the mechanism and projects from the transmissionas shown at I2. The pressure plate is normally held retracted byretractor springs I3. This particular clutch construction is more fullydescribed and claimed in application Serial No. 291,574, filed August23, 1939, now Patent No.'2,371,564, issued March 13. 1945, and nofurther detailed description is needed herein. Suiiice it to say thatthere are a number of circumferentially arranged levers, preferablythree, and a plurality of circumferentially arranged retractor springs.The clutch is disposed in a clutch housing generally shown at I4.

Next adjacent the clutch housing is a housing or compartment 20 whichAcontains the hydraulic system including a hydraulic pump and controlvalves. Next adjacent the chamber 20 is a gear change transmissionindicated at 2 I. This transmission may be o1 a conventional type forproviding three forward speeds: namely, low, intermediate and high, `andone speed in reverse. Of course, the transmission provides for a neutralcondition where no driving connection exists in the transmission. Inthis `ansmission the train of gears for the low gear atlo embodies anoverrunning coupling so that when the transmission is conditioned forthe intermediate or the high gear ratio the overrunning coupling of thelow gear train functions to permit overrunning action ofl some of thegears of the low gear train so that these gears may remain in mesh witheach other while the torque is transmitted through the higher gearratios. This is a conventional transmission construction and needs nofurther disclosure or explanation.

As stated above, the clutch shaft III extends freely through thetransmission. The torque output member for the transmission is shown at22 in the form of-a sleeve surrounding the rear end of the clutch shaftand mounted thereon is the outer member 23 of a one-way drive coupling.as shown in Fig. 3. The inner member of the one-way driven coupling at24 is mounted on the clutch shaft. As shown in Fig. 3, the outer member23 has recesses 25 for receiving rollers 26 designed to cooperate withnotches 21 on the inner member 24. In the normal operation while theoutput member 22 is driving the vehiclel the rollers 26 are heldoutwardly in their pockets centrifugally and are ineffective. The normaldirection of rotation of the parts is counterclockwise as Fig. 3 isviewed, and it will be seen that the clutch shaft will not drive themember 23 as the rollers are cammed up the long angular faces of thenotches 21. However, when the parts are at rest and a movement is givento the vehicle, one of the rollers will gravitate into a compressivelyengaged condition between a wall of its notch 25 and the abrupt wall ofone of the notches 21 so that the clutch shaft will be driven in acounter-clockwise direction as Fig. .3 is viewed. The purpose of this isfor an emergency starting of the engine by towing or pushing thevehicle, as will be more fully understood as the detailed descriptionprogresses.

The chamber 20 for the hydraulic pump is defined by a partition 30 andpartition 3l which divides oil the clutch housing and the transmission.The transmission input member 32 is journalled in the partition, as at33, and suitable seals are used as at 34 and 35 where the clutch shaftand the power input member extend through these partitions. The inputmember 32 has a gear formation 36 which drives a gear 31 on acounter-shaft which is journalled in the partition 3I as at 38 and atthe rear end of the transmission case, as shown at 39. The pump has abody generally shown at 40, in which is journalled a shaft 42 coupled tothe gear 31, and a suitable seal structure 43 is employed to seal thehousing. As shown in Fig. 11, the pump is in the form of a gear pumphaving two gears 46 and 41 for moving oil through the inlet 48 to theoutlet or lhigh pressure side of the pump at 49. The pump is preferablysubmerged in the liquid or oil, the normal level of which may be asindicated at 50. The outlet side of the pump is provided with a pressurerelief valve 5I as shown in Fig. 11.

The high pressure side of the pump is connected to deliver liquid underpressure to several operating elements. These include a piston andcylinder arrangement for acting upon the friction clutch so that theclutch may be engaged hydraulically and so that the hydraulic pressuremay supplement centrifugal force in engaging the clutch. Also, the highpressure side of the pump is connected to a piston and cylinderarrangement for controlling the power coupling and to a cylinder andpiston arrangement for causing a change of gearing in the transmission.Control valves are located in the high pressure line to effect a propercontrol and operation of these hydraulically actuated elements.

The power coupler control cylinder is illustrated in Figs. 7 and 8, thecylinder being shown at 55, its piston at 56. and its strut-likeconnecting rod at 51. Fig. 8 shows the piston shifted hydraulically tothe limit of its movement.

The clutch actuating cylinder is shown in Fig. l, the cylinder beingillustrated at 60 mounted in the partition 30 and having a Ipiston 6Itherein. The head of the cylinder 62 has an extension 63 and the pistonhas a sleeve 64 which slides through an adjustable head 65 and cars rieson Aits exposed end an anti-thrust bearing 00.` A spring 01 normallyurges the piston to the right as Fig. 1 is viewed. When the piston is-shifted to the left by liquid under pressure, the anti-friction bearingengages the levers 4 and swings them to causeclutch engagement or tosupply supplementalclutch engaging pressure. The head 65 is screwthreaded in position and may be adjusted in order to vary the stroke ofthe piston to take up the wear of the facings 0. The bearing 66 limitspiston movement striking `the head 55 and a shoulder 58 limits movementof the piston in clutch engaging direction. The

`head of the cylinder is vented as at 10 to prevent trapping of air. Thehead 52 of the cylinder has a passage 1| therein (Fig. 12) connected asare shown in Figs. 9 and 10. The cylinder 15 is double ended and haspassages 16 and 11 leading to its opposite ends. The piston 10 lismounted on a reciprocatory rod 10 connected to a shifter 99 of thetransmission as at 80. The shifter 09 is operable to effect differentgear ratios between the power input member 32 and the power outputmember 22 in the usual manner of a gear change transmission. The pistonLs preferably balanced in the cylinder by opposed springs and 82. In theneutral or central position, the parts are shown as in Fig. 10. When thepiston is shifted in one direction the parts are as illustrated in Fig.9. There is a detent 82 which functions in notches 83 in the plston 16and which serves, under certain condi'- tions, to mechanically lock thepiston in any one of the three positions of adjustment.

Considering, now, the control valve system, which includes thecontrolling valves located between the pump and the several servocylinders. The high pressure'line 40, as shown in Fig. 11, comprisesvarious tubing connections which are necessary for assembly purposes butthe character I0 is applied to all portions of this high pressure line.As shown in Fig. 13, a valve chamber 64 is positioned between the highpressure line 49 and the connection 12 to the clutch servo cylinder, andin this chamber is a valve with a port 86. Shift of this valve throughabout 90 causes the port 86 to connect ports 01 and 09. In the positionshown, the high pressure line is closed and the cylinder is open to theexhaust port 90. A low pressure relief valve is shown at 9|and which isconnected to the high pressure line at the same time the clutch servocylinder is connected to the high pressure line. Details of this valveare set forth in a` separate application and suiiice it to say here thatit maintains a desired low pressure in the system while it is connectedto the pump outlet. Rocking movement of the valve v| maybe limited bythe stop. 92 functioning in conjunction with stop pins 83 (Fig. 14). Thevalve 85 is also ported at 85 so that it may connect the power couplercylinder with the high pressure line through the means of ports 86 and81 and connect the power coupler cylinder with the discharge port 88(Fig. 7). 4

It will be observed by reference to Fig. 6 that the valve 85 isconveniently located on one side of the center line while two othervalves are mounted on the opposite side of the center line.' Qne ofthese valves, namely, the upper valve |00 may be called the selectorvalve .while the other valve |0| is a form of control valve and thesetwo valves work in conjunction with each other. They control theadmission and discharge of liquid to and from the opposite ends of thetransmission servo cylinder 15. As shown in Fig. 15 the valve |0| ispositioned between the high pressure line 48 and the chamber of thevalve |00. The valve |0| is ported at |02 so that it may connect thehigh pressure line 40 and the chamber of valve |00. In the location ofthe section of Fig. 15 the valve |00 is doubly ported at |04 and |05.In'the position shown it closes the port from the chamber of valve |00and, therefore, closes from the high pressure line the passage 11 and16. This valve is movable to the position shown in Fig. 15b in whichposition it may connect the high pressure line to the passage 11 so thathigh pressure liquid may be connected to the cylinder 15 (Fig. 9). 'Ihisvalve may be moved to the position as shown in Fig. 15e, so as toconnect the high pressure line to the passage 16 and, accordingly, tothe opposite end of the transmission servo cylinder.

The two valves are similarly formed at another location, as shown inFig. 16, the valve |00 being doubly ported at |08 and |09 and the valve|0| is ported so as to connect to a discharge port ||0. Considering Fig.16, ifthe valve |00 is moved approximately 45 counter-clockwise, thepassage 11 maybe connected to the discharge port H0, if the controlvalve |0| permits. If the valve. |00 is shifted to approximately 45clockwise, the passage 16 may be connected to the discharge port ||0 ifthe valve |0| permits.

As shown in Fig. 17, the valve |0| is held against axial movement by apin ||2; the valve |00 is held against axial movement by a pin ||3 andthere is a spring pressed detent H4 which functions in three sets ofnotches ||5 located in the sides of the groove provided for the pin ||3.As shown in Figs. 9 and 10 the valve |00 is doubly ported as at ||6 and||1, while at this location the valve |0| has a circumferential groove||8 in constant communication with a discharge port ||9. The ports ||6and ||1 are arranged to register with the ports leading to the passages16 and 11.

As illustrated in Fig. 15a, when the valve |03 is positioned so that itblocks off the high pressure line, the ports ||6 and ||1 are positionedto discharge liquid from both ends of the transmission servo cylinderthrough the control valve |0| and port H9. When the selector valve |00is positioned as shown in Fig. 15b, with the port |05 positioned todirect high pressure liquid into passage 11, and thus into the left handend of the transmission servo cylinder, as Fig. 10 is viewed. the lefthand end of the cylinder connecting the passage 11 is closed. But, theright hand end of the cylinder is exhausted through the ports ||6 and||1. When the selector valve is positioned, as shown in Fig. 15o, theport |04 connects the high pressure liquid to therpassage 16 and theright hand end of the transmission servo cylinder as Fig. 10 is viewed,while the ports ||1 and ||8 exhaust the opposite end of the cylinder.

The actuating mechanism for these valves is shown in Figs. 6 through 10,inclusive. For the valve 05, there is a shaft |25 which, through an arm|26 engaging a pin on arm |21, rocks a cross shaft |20. This shaft hasan arm |29connected by a link |30 to an arm |3| on the valve. A coilspring |3| keeps the valve normally positioned in a manner presently tobe brought o-ut. For the selector valve |00 there is a shaft |35 with anarm Before going into a description of the operatorA actuated controlmeans for these valves and the other functions of the hydraulic system,a disclosure of the powe; coupling appears to be appropriate inasmuch asthis coupling is lccated in the housing 20. This particular coupling isof the type described and ciaimed in application Serial No. 291,574,and, accordingly, a brief description herein will suffice. As mentionedabove, the clutch shaft extends freely through the transmission. Thepower coupler is located between the clutch shaft and the transmissionpower input member 32. The clutch shaft has a hub member |50 with amember thereon which is the driving member of the power coupler, thismember being shown at |5| and it has teeth 52. The powe input member 32has a sleeve formation with a spline structure thereon of helical natureand in the present arrangement the spline is left handed, as shown at|53. Mounted on these splines is a coupler member |54 with a groove |55for receiving the shoes on the yoke |40. This coupler is acted upon by aspring |56 and it has teeth |51 for dental engagement with the teeth|52. There is a bumper of rubber or the like |58 for striking thedriving member |5|. Accordingly, it will be noted that the drivingmember |5| is coupled to the clutch shaft whereas the dziven member isthe power input member 32.

Means are provided for permitting a. dental engagement between the teeth|52 and |51 only when the parts `are substantially synchronized. Asshown in Fig. 20, there is a blocker ring |60 loosely splined n thepower input member 32. This member has cam surfaces |6| and rollers |62cooperate between the cam surfaces and the internal peripheral surfaceof the driving member The rollers are located as by means of a cage |63and the cage has depressed portions |84 which ride in a groove in theblocker ring |60 to keep the cage axially centered. There is a coilspring |65 with one end engaging the power input member 32, as shown inFig. 18, and with its other end engaging the -blocker ring |60, as f5shown at |66 (Fig. 20), and this spring normally loads the blocker ringso as to hold the blocker ring in the position shown in Fig. 21. In thisposition the blocker ring is held relatively counter-clockwise to thelimit of its movement on the loose splines. There is another coil springwhich has its ends connected respectively to the blocker ring and to thecage. This spring acts upon the cage and urges it relatively clockwiseand so tends to wedge the rollers in between the cam surfaces |6| andthe inner peripheral surface of the drive member |5|. On the couplermember |54 are blocker abutments or blocker teeth and there may be threeof these as shown in Fig. 20.

When the coupler member and the driving member |5| are disengaged asshown in Fig. l, and in Fig. 19, the blocker ring |60 is urgedcounter-clockwise or, in other words, from the Fig. position to the Fig.21 position. The

' blocker ring has blocking portions nl which pass in front of theblocking elements |1I. as shown in'Fig. 2l. With the parts in thesepositions, a dental engagement cannot be made since the coupler |54cannot shift toward the driving member |5|. When, however, the blockerring is shifted from the position shown in Fig. 21 to the position shownin Fig. 20, the parts |12 move out of blocking position and the blockingteeth |1| may pass into the clearance ways |13 in the blocker ring andthe teeth |51 may thereupon move into engagement with the teeth |52.

The operation of this power coupling is, briefly, as follows: When theparts are coupled, as shown in Fig. 18, the clutch shaft I0 may drivethe power input member of the transmission 32 through the dentalengagement and the coupler. When the parts are in a position shown inFig; 19, the clutch shaft |0 is free of the power input `member 32 andthere is no driving connection. The normal direction of rotation ofparts is clockwise as Figs. 20 and 21 are viewed. As long as the drivingmember |5| is operating at a speed lower than that of the power inputmember and, therefore the coupler |54 (or the driving member may be atrest), the blocker ring maintains the position shown in Fig. 21. When,however, the driving member comes up to the speed of the coupler memberand then tends to overrun the coupler member the overrunning clutchrollers 62 take hold and rock the blocker ring from the Fig. 21 positionto the Fig. 20 position. Thereupon, unless the parts are otherwiserestrained, the spring |56 shifts the coupler |54 to the left as Fig. 19is viewed and the teeth |52 and |51 become dentally engaged. In thisaction the blocker elements |1| move into theclearance ways |13. Now,inasmuch as the teeth |52 and |51 may be straight and a period of timeis needed to complete the dental engagement, the helical splines areprovided which permits the coupler to rotate with the driving member asthe teeth are sliding into full engagement before it picks up the loadof the power input member.

:. The load is picked up and torque is transmitted when the bumper |58strikes the driving member |5| and stops axial movement of the coupler.It will be noted that both the driving member |5| vand the power inputmember 32 may be under load, the one being coupled to the engine and theother being coupled to the traction wheels.

Proceeding now to the control means for the operator or driver as shownin Fig. 4. There is a direction lever diagrammatically shown in Fig. 4.This lever may be conveniently positioned in the drivers compartment.This lever is connected through the linkage shown to a control arm |8|of the gear shift transmission and there may be three positions. Thecenter position may be neutral, in which there is no connection in thetransmission; one position may be reverse which connects the reversegears in the transmission; the other position is for forward whichconnects the low gear train in the transmission for a. forward drive. Itmust be remembered at this' point that the low gear train embodies anoverrunning coupling or clutch.

There is a selector lever |82 connected by the link, as shown, to thecontrol shaft |35 for the selector valve |00 (see Fig. 6). This leverhas three positions as indicated, namely, a neutral position andpositions for two other forward gear ratios which may be termed secondgear and u third or high gear. It should be remembered at this pointthat the lever |80 establishes a low gear drive.

The throttle member vor accelerator treadle is shown at |84 connected bya link |85 to a rock shaft |86. An arm |81 is mounted on the rock shaftthrough the means of a one way coupling and a torsion spring |88 andthis arm is connected through a link |89 to the valve controlling shaft|25. The hub of arm |81 has one half cut away as at |95 for a one wayconnection with a key as shown in Fig. 5. Another arm |90 is connectedto thefuel supply or carburetor for the engine. This connection may bethrough a link |9| which has a 10st motion connection at |92 with thethrottle control arm |93 of the carburetor |94 having a throttle valve|95. With this arrangement the throttle member |84 may move to theposition y before there is any movement imparted to the carburetorcontrolarm |93 and during this movement the arm |81 moves from theposition shown to a position at about :r for shifting the shaft |25 forthe control valves. The operation of the mechanism is as follows: Withthe engine of the vehicle idling, say about 500 or 600 R. P. M., thecentrifugal clutch is disengaged. This clutch may engage centrifugallyat about 700 or 800 R. P. M. Preferably, the centrifugal weight systemis of relatively light construction and not capable of transmittingmaximum engine torque up to speeds of rotation of about 1800 to 2000 R.P. M. This promotes smoothness of clutch engagement and the clutchpacking pressure is supplemented hydraulically by the piston 6|. Withthe direction lever |80 positioned in neutral the transmission 2| is inneutral and the engine may be accelerated as desired without impartingany torque to the traction wheels. If it is desired to move the vehicleforward, the direction lever |80 is shifted to the forward position.This establishes a connection through the low gear train in thetransmission with the overrunnng or one-way drive coupling.

The selector lever may be positioned inthe central position which isboth neutral and .first speed. In this position, the selector valve isdisposed as shown in Fig. a with the high pressure line closed off fromthe gear shift servo cylinder 85 and with both ends of the clutch servocylinder discharged of liquid tothe sump through the ports H6 and H1.Therefore, the piston 18 is in the middle position as shown in Fig.` 10and the connection 80 is in the neutral position. as shown in Fig. 4.When the treadle |84 is depressed it first moves through the lashmovement or lost motion or to the position y and .this rocks the controlshaft and through the linkage. above described, rocks the control valve85. The normal position of the control valve 85 is as shown in Fig. 1 3where the high pressure line is cut off from the clutch servo cylinderand, as shown in Fig. 8, where the high pressure line is connected tothe power coupler control cylinder 55. In the lash movement of thetreadle, the valve 85 is shifted about 90 counter-clockwise as Fig. 13is viewed. This connects the clutch servo cylinder with the highpressure line of the pump. This movement of the valve, clockwise as Fig.

- 8 is viewed, disconnects the high pressure line v tation of the shaftI0, a dental engagement of the power coupling will be made as this ispermitted due to the fact that the high pressure liquid is cut ofi fromthe cylinder 55. This will then drive the power input member 32 andtransmit power to the output member 23 and cause the vehicle to moveforward in low gear. At the same time, the pump will start to operateand liquid under pressure is conveyed to the cylinder and the clutchpacking pressure is augmented hydraulically. Under these conditions, adesired low pressure is maintained in the hydraulic system by the lowpressure relief valve 9|. Since the accelerator is depressed beyond theposition y the cam |45 is rotated so as to engage the detent 82 and thusthe gear shift servo piston is locked mechanically in its intermediateor neutral position. If the accelerator is allowed to retract the valve85 is restored to the position shown in Figs. 13 and 8. This cuts offthe hydraulic pressure to the clutch servo cylinder and allows liquid'under pressure to enter the cylinder 55. This action causes the piston50 to shift and to rock the yoke |40, which shifts the coupler element|54 to disengage the teeth |51 and |52.

Now, any time that the vehicle is being operated in low gear, theselector lever |82 may be shifted into either second gear or third gearpositions. Suppose, for example, it is shifted to the second gearposition; this moves the valver |00 from the set of conditions shown inFig. 15a to the set of conditions shown in Fig. 15b. The selector valveis now conditioned for the entrance of liquid under pressure into thegear shift servo cylinder through port |05 and passage 11, andconditions the valve for the discharge of the opposite end of thecylinder through passage 18 and ports I6 and ||1. Nothing happens,however, because of the control valve |0|. When the accelerator treadleis depressed the port |02, as shown in Fig. 15, is in the dotted lineposition and, therefore, closes oiT the high pressure line; the port|02a, shown in Fig. 16, is in the dotted line position and is,therefore, in a position to exhaust the gear shift servo cylinderthrough the line 11 but the cylinder is already exhausted of highpressure. Movement of the selector valve to the second gear positionmerely conditions the selector valve |00, as shown in Fig. 15b, with noattendant to function. However, when the accelerator treadle isreleased, the pressure liquid is introduced into the power couplercontrol cylinder55 through port 95 of valve 85 (Figs. 7 and 8) thisshifts the yoke and breaks the power coupling and through the arm |43rocks the control valve |00 to the full line positions shown in Figs. l5and 16. Port |02, therefore, connects the high pressure line with thepassage 11 through port |05 and the piston 18 is shifted to establishthe second gear ratio. This shift is permitted because the deteni'l 82was released when the treadle was allowed to retract. Inasmuch as theport`|09 (Fig. 16) is in a position to exhaust passage 11 there would beno pressure built up to shift the piston 18 if this exhaust conditioncontinued. But, the port |02a has, upon retraction of the accelerator,moved to the full line position and this closes the exhaust line for thepassage 11 and the left hand end of the cylinder 15, as Fig. l0 isviewed. Upon depression of the accelerator, vafter the second gear ratiohas been established, the liquid under pressure is transmitted throughvalve 85 to the clutch servo cylinder (Fig. 13), and the pressure liquidis cut off from the power coupler control cylinder (Fig. 7) and thevalve IUI is moved to the dotted line positions shown in Figs. 15 and16. Port |02. therefore, is positioned to close the high pressure lineand port |02a is positioned to exhaust the left hand end of cylinder 15through the passage 11 and the exhaust port H0. Accordingly, thecylinder 15 is exhausted of liquid from both ends during all normaldriving. Note, however, that upon depression of the accelerator thepiston 18 is mechanically locked in position by the detent 82.

Now, when the vehicle is moved forward ln low gear, or in second gearfor that matter, the selector lever |82 may be shifted to the third orhigh speed position. This conditions the selector valve to the set ofconditions shown in Fig. l5c. In other words, the valve |80 is shiftedapproximately 45 clockwise from the full line position shown in Figs. 15and 16. When the accelerator is retracted which cuts off the pressureliquid from the clutch servo cylinder and supplies liquid to the powercontrol cylinder, the resultant shift of the yoke breaks the powercouplings and shifts the control valve |8| so that its ports |02 and|02a take the full line positions shown in Figs. 15 and 16. Thisintroduces pressure liquid through the passage 18 and shifts the piston18 to the left, as Fig. 1G is viewed, thus shifting the transmissioncontrol 80 to the third or direct drive position. At this time, ofcourse, the left hand end of the cylinder 25 remains exhausted.Moreover, the right hand end of the cylinder 15, as Fig. is viewed, isclosed by reason of the disposition of the port |0211. When theaccelerator is depressed the valves are shifted through the lashmovement so that control valve |0| moves back to the positions shown infull lines in Figs. and 16 and this closes off the high pressure lineand discharges liquid from the gear shift servo cylinder through passage16, port |02a and discharge port lili. The transmission servo piston isagain mechanically locked by the detent 82.

Briefly reiterating this operation without a detailed reference to thevalves, assume that the engine is idling; with the direction lever |80in neutral position the engine may be accelerated as desired with notorque transmission to the traction wheels. To go forward, all theoperator needs to do is shift the direction lever to the forwardposition. If the selector is in its middle position, as shown in Fig. 4,the vehicle will move forward upon depression of the accelerator. Thismovement will be in low gear. During vehicle movement in low gear theselector lever may be shifted as desired either to the second gearposition or the third gear position. Then upon allowing the treadle toretract, the power coupling is broken hydraulically and the transmissionis shifted hydraulically either into second or third gears dependingupon which was selected. Then, upon depression of the accelerator, thepower coupling is established and the car is propelled forwardly in theselected gear ratio. Each time the accelerator is depressed, liquid istransmitted to the cylinder 60 to provide supplemental clutch packingpressure; each time the accelerator is depressed liquid under pressureis 'cut off from the power coupler control cylinder55 so that the powercoupling engages when the driving member tends to exceed the R. P. M. ofthe driven member. Each time the accelerator is depressed liquid underpressure is cut off from the gear shift servo cylinder 15 and the end ofthe cylinder, which was just previously supplied with liquid underpressure, is dumped of its liquid through the port |8211. Each time theaccelerator treadle is retracted to the full line position, shown inFig. 4, liquid under pressure is cut off from the clutch servo cylinder60; liquid under pressure is admitted to the power coupler controlcylinder 55; the cam |45 unlocks the detent 82; and liquid underpressure is delivered to the gear shift servo cylinder 15 as determined,however, by the selector valve. This is a pre-selection and when theselector valve is in the position, shown in Fig. 15a, no liquid entersthe gear shift servo cylinder. If the selector valve is moved to thecondition shown in Fig. 15b, the transmission servo piston is moved toshift the transmission into second gear; if the selector valve has beenpre-selected into the position shown in Fig. 15e the piston moves toshift the transmission into high gear. To reverse the vehicle thedirection lever is shifted to reverse position and this closes thereverse gear train, so that upon the depression of the accelerator, aconnection is established at the power coupler and the vehicle is movedin reverse.

So, it will be seen that in the normal forward operation of the vehiclethe operator merely preselects the gear desired by shift of the lever|82 and this gear ratio is established upon release of the treadle. Withthe direction levelI in forward position, the vehicle will always moveforward upon depression of the treadle because the intermediate positionof the selector lever connects the low gear train.

The mechanism provides a semi-automatic operation. A. driver may operatethe vehicle over long periods of time by controlling the same entirelyby manipulation of the accelerator treadle. An example of this is asfollows: Suppose the driver of an automotive vehicle is operating thevehicle in direct drive and it is necessary to bring the vehicle to astop because, for example, of traffic regulations. 'I'he direction leveris in forward position and the selector lever is in direct driveposition. The accelerato;- treadle is allowed to retract and the vehiclemay be brought to a stop by an application of the brake. When theaccelerator fully retracts, the mechanical lock or detent 82 for thepiston 18 is released by the cam |45. Before the vehicle comes to a stopthe centrifugal clutch disengages. The centering springs 8| and 82 shiftthe transmission piston 80 to its intermediate or neutral position.There is a loss of pressure liquid in the hydraulic system. Now, upondepression of the accelerator treadle the vehicle moves forward in lowgear and the pump is actuated for setting up liquid pressure. As soon assufcient speed is attained the accelerator is allowed to retract and thetransmission is shifted into direct gear. This occurs because theoperator has not disturbed the selector lever or the direction lever.

It will be noted that the pump is driven by gear 31, which in turn isdriven by the transmission input member 32 and that the power couplingis located between the input member and the engine. The arrangement,however, provides for continued operation of the pump under certainconditions where the power coupling is disengaged. When, in theoperation of the vehicle, the functions are such that the power couplingbecomes disengaged, the pump is operated by the movement of the vehiclewith the torque transmitted through the transmission if the transmissionis in gear. When the transmission is in neutral, however, the movementof the vehicle does not drive the input member l2; if the power couplingis disengaged the engine cannot drive the input member 32 through thecoupling. In this case, the overrunning clutch comprising the rollers|62 function to drive the input member 32 and, therefore, the pump.vThis will occur so long as the friction clutch is engaged eithercentrifugally or hydraulically. By referring to Fig. 20, it will beappreciated how clockwise rotation of the driving member is transmittedthrough the rollers |62 which engage the inclined surfaces IBI. limit ofits loose spline connection on the member 32 where it picks up anddrives the member 32. Thus, the construction shown in Fig. 20 not onlyserves the function of controlling the blocking action for the powercoupler but serves, under certain conditions, to drive the pump of thehydraulic system.

In the event the engine is stalled and it is desired to start it bytowing or pushing the vehicle, the coupling across the rollers 28 isestablished. One of the rollers gravitates and becomes compressivelyengaged in the notches as the member 23 rotates counter-clockwise asFig. 3 is viewed. This drives the clutch shaft I0. If the transmissionis in gear, the pump may be driven directly through the member 32 to themember 31. If the transmission is in neutral the driving member |5| ofthe power coupler will rotate clockwise as Fig. 20 is viewed and pick upthe blocker ring |60 This rocks the blocking element |60 to the by theoverrunning rollers |62 to cause turning of the member 32 and therebydrive the pump. Operation of the pump will, upon depression of theaccelerator, cause liquid under pressure to be transmitted into thecylinder 60 to shift the piston and cause engagement of the frictionclutch to thus rotate the engine.

I claim:

1. In a mechanism for the transmission of power from an engine to thetraction wheels of an automotive vehicle or the like comprising incombination, a centrifugal clutch arranged so that it is open at engineidling speeds and engageable centrifugally upon acceleration of theengine above idling speeds, a gear change transmission having a powerinput member and a power output member and shiftable means to effectdifferent gear ratios between said members, a power coupling between theclutch and the input member of the transmission, a throttle member forthe engine, power means for disengaging the power coupling and actuatingthe shiftable means of the transmission, and means under the control ofthe throttle member for setting the power means into action when thethrottle member is actuated to cut the power of the engine.

2. In a mechanism for the transmission o! power from an engine to thetraction wheels of an automotive vehicle or the like comprising incombination, a clutch of anautomatic type constructed and arranged sothat it is disengaged at engine idling speeds and so that it engagesupon acceleration of the engine above idling speeds, a gear changetransmission having a power input member and a power output member andshiftable means to effect different gear ratios between said members, apower coupling between the clutch and the input member of thetransmission, a throttle member for the engine,rpower. means fordisengaging the power coupling and actuating the shiftable means of thetransmission, and means under the control of the throttle member forsetting the power means into action when the throttle member isactutated to cutthe power of the engine.

3. In a mechanism for the transmission of power from an engine to thetraction wheels o1' an automotive vehicle or the like comprising incombination, a centrifugal clutch arranged so that it is disengaged atengine idling speeds and engageable centrifugally upon acceleration ofthe engine above idling speeds, a gear change transmission havingshiftable means effective for changing gear ratios, a coupling betweenthe clutch and the transmission, a throttle member for the engine, powermeans for opening the coupling and for shifting the shiftable means ofthe transmission, and means under the control of the throttle member forsetting the power means into action when the throttle member is moved tocut the power from the engine.

4. In a mechanism for the transmission of power from an engine to thetraction wheels of an automotive vehicle or the like comprising incombination, a driving member operated by the engine, a gear changetransmission having a power input member and a, power output member andshiftable means to effect different gear ratios between said members, apower coupling between thesaid driving member and the power input memberof the transmission, a throttle member for the engine, power means foropening the coupling and for shifting the said shiftable means of thetransmission and means under the control of the throttle member forsetting the power means yinto action as the throttle member is actuatedto cut the power from the engine, the power means being renderedAineffective as the throttle member is depressed for engineacceleration, and means for establishing a connection at the powercoupling between the said driving member and the said power input memberofthe transmission upon acceleration of the engine.

5. In a mechanism for the transmission of power from an engine to thetraction wheels of an automotive vehicle or the like, comprising incombination, a driving member operated by the engine, a gear changetransmission having a power input member, shiftable means for thetransmission for changing gear ratios, a coupling between the drivingmember and the input member, a hydraulic system including a pump,cylinder and piston means in the hydraulic system operable upon thecoupling and upon the shiftable means of the transmission, meansdrivingly connecting the power input member and the pump, synchronizingmeans for the coupling including means for establishing a torquetransmitting connection between the driving member and the input memberwhereby to drive the pump when the coupling is open and the transmissionis in neutral.

6. In a mechanism for the transmission of power from an engine to thetraction Wheels of an automotive vehicle or the like, comprising incombinat'on, a gear change transmission having a shiftable member, acoupling arranged to be engaged and disengaged, the transmission andcoupling being disposed between the engine and the traction wheels, ahydraulic system including a pump and means operable hydraulically foracting upon the coupling and the shiftable member of the transmission,controlling valves in the hydraulic system, a throttle for the engine,said valves being operated when the throttle is actuated to cut thepower of the engine for disengagement of the coupling and for shift ofthe shiftable member of the transmission to effect a change of gears,said valves being operated when the throttle is actuated to cause powerto be delivered from the engine for engagement of the coupling and to 15render the hydraulic system ineffective upon the shiftable member of thetransmission, and mechanical means effective when the throttle isactuated to cause power to be delivered from the engine for locking thetransmission in a given position.

7. In a mechanism for the transmission of power from an engine to thetraction wheels o1' an automotive Vehicle or the like, comprising incombination. a gear change transmission having a shiftable member, acoupling arranged to be engaged and disengaged, the transmission andcoupling being disposed between the engine and the traction wheels, ahydraulic system including a pump and means operable hydraulically foracting upon the coupling and the shiftable member of the transmission,controlling valves in the hydraulic system, a throttle for the engine,said valves being operated when the throttle is actuated to cut thepower of the engine for disengagement of the coupling and for shift ofthe shiftable member of the transmission to eiTect a change of gears,said valves being operated when the throttle is actuated to cause powerto be deliv- 16 e ered from the engine ior engagement of the couplingand to render the hydraulic system ineffective upon the shiftable memberof the transmissionI and mechanical means operated by the throttle forlocking the transmission in a given position when the throttle isactuated to cut the power oi' the engine.

ERNEST E. WEMP.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,818,910 Sanine Aug. 11, 19312,159,170 Maybach May 23, 1939 2,171,534 Banker Sept. 5, 1939 2,234,463Brewer Mar. 11, 1941 2,292,253 Thurber Aug. 4, 1942 2,296,290 MayrathSept. 22, 1942 2,297,026 Y Sanford et al Sept. 29, 194': 2,349,297Neracl'er et al May 23, 1944 2,353,137 Banker July 11, 194A

